All the hard work is done for you, you just have to get familiar with the code and start using it. It's very simple, you just figure out how many columns you need and use class="" with very simple and easy to remember nomenclature.

Oh, and free. always good!

cybersa

Thanks for your suggestion.

I fixed mind to go with Responsive design with Flat Design.
I need to create good layout which should better for all screen.

@Pande
Thanks for your link.
Currently i checked Twitter Bootstrap.
It also nice.

Is any other best tool available which is easy to learn like Bootstrap?